Standards of diagnostic assessment for autism spectrum disorder.

The rising prevalence of autism spectrum disorder (ASD) has created a need to expand ASD diagnostic capacity by community-based paediatricians and other primary care providers. Although evidence suggests that some children can be definitively diagnosed by 2 years of age, many are not diagnosed until 4 to 5 years of age. Most clinical guidelines recommend multidisciplinary team involvement in the ASD diagnostic process. Although a maximal wait time of 3 to 6 months has been recommended by three recent ASD guidelines, the time from referral to a team-based ASD diagnostic evaluation commonly takes more than a year in many Canadian communities. More paediatric health care providers should be trained to diagnose less complex cases of ASD. This statement provides community-based paediatric clinicians with recommendations, tools, and resources to perform or assist in the diagnostic evaluation of ASD. It also offers guidance on referral for a comprehensive needs assessment both for treatment and intervention planning, using a flexible, multilevel approach.